280zx distributor upgrade in 280z, tach now doesn't work

[siteunseen]

The ZX coil is lower ohms.

 

[Ownallday]

6 minutes ago, Zed Head said:

Those wires, the red and green, actually went to the old distributor and the ignition module under the dash.  They are the trigger wires.  Not used anymore because all of that is contained in the ZX distributor now.

If the engine starts and runs properly and the tach needle is twitching then odds are the connections are correct.  The blue wire supplies both the ECU and the tach with the spark signal, to fire the injectors and run the tach.  They're on the same wire.

Might also be that your new coil is "noisy".  Might be worthwhile to swap the old coil back in, just to see.  The coil is the other thing that is different now.

Okay that's what I figured, couldn't exactly remember. so I should remove the Black/White wire on the positive terminal since its not doing anything.

 

Engine starts perfectly and runs perfectly despite having new untuned webers out of the box. Spark is extremely good too. The Tach does twitch when turning the key to the on position which it use to do with the stock setup.

 

Okay I will test the old coil later and let you know if the results are the same or different. My car is open headers atm so im not trying to wizz off the neighbors with multiple constant starts haha.

4 minutes ago, siteunseen said:

The ZX coil is lower ohms.

 

So the coil could be at fault here? I heard most people don't have problems using the MSD coil however but I am unsure

[Zed Head]

9 minutes ago, Ownallday said:

So the coil could be at fault here? I heard most people don't have problems using the MSD coil however but I am unsure

One of the basic rules of torubleshooting a new problem is to go back and look whatever changes were made before the problem showed up.  A coil swap is simple and will take that possibility out of the equation.  As far as the coil goes, factory parts are almost always of better quality than aftermarket.  MSD is not even owned by MSD anymore.  It's a brand name, owned by Holley. 

And Holley was purchased by private equity back in 2012, after they went bankrupt a couple of times.  Private equity firms are all about profit.  Basically, MSD and Holley and most of the big auto names many of us grew up with are really just brand names now, parts are manufactured wherever the cheapest labor is.

Sorry.   Hate to be a downer...

https://www.holley.com/brands/msd/

https://en.wikipedia.org/wiki/Holley_Performance_Products

Edited December 6, 2020 by Zed Head

[Zed Head]

And, I don't think is your problem, if you do get it working with the Blaster coil, see below.

https://www.summitracing.com/parts/msd-8202

 

[siteunseen]

I'm not saying the brand is bad just the ohm rating is lower. Whether that plays into your problem I have know idea. Sorry for any confusion. Personally I run a 1.0 ohm Crane ps20 Fireball with my e12-80.

[Ownallday]

20 minutes ago, Zed Head said:

One of the basic rules of torubleshooting a new problem is to go back and look whatever changes were made before the problem showed up.  A coil swap is simple and will take that possibility out of the equation.  As far as the coil goes, factory parts are almost always of better quality than aftermarket.  MSD is not even owned by MSD anymore.  It's a brand name, owned by Holley. 

And Holley was purchased by private equity back in 2012, after they went bankrupt a couple of times.  Private equity firms are all about profit.  Basically, MSD and Holley and most of the big auto names many of us grew up with are really just brand names now, parts are manufactured wherever the cheapest labor is.

Sorry.   Hate to be a downer...

https://www.holley.com/brands/msd/

https://en.wikipedia.org/wiki/Holley_Performance_Products

Well it came down to the coil! Put the stock one back on, fired up the car and what do you know, tach now shows where my car is idling at! So my question is, if I want to stick with the MSD unit, could I just add a potometer or a resister to the blue Tach wire and get it to work like that? To my knowledge I was told to upgrade to MSD or something similar with the ZX dizzy and Triple weber setup. I plan on getting the MSD 6AL in the future so I know once I do that my tach will need to be hooked up completely different.

[Zed Head]

Paint the factory coil red and put a Blaster sticker on it?  Or just save the blaster for use with the 6AL.

Thanks for coming back with the solution.  Nice when a guess turns out right.  It is odd, really, that the Blaster doesn't work.  

A condenser on the negative wire might get the Blaster working but, why bother?

[Ownallday]

15 minutes ago, Zed Head said:

Paint the factory coil red and put a Blaster sticker on it?  Or just save the blaster for use with the 6AL.

Thanks for coming back with the solution.  Nice when a guess turns out right.  It is odd, really, that the Blaster doesn't work.  

A condenser on the negative wire might get the Blaster working but, why bother?

Haha, not a bad idea. Ill most likely just save for the 6AL, I plan on doing it very soon anyways.

I don't like finding posts without a solution so I will always post the solution on my threads. Thanks for the help, now to make a new thread if my jetting is proper for my Engine setup

[Patcon]

Jist remember going to the 6AL isn't going to gain you a lot. It will also make you car less stock which makes it harder to diagnose.

If I wanted to make power, reworking the ignition would be pretty far down the list. Provided I wasn't running points...

Edited December 7, 2020 by Patcon

[Ownallday]

On 12/6/2020 at 7:28 PM, Patcon said:

Jist remember going to the 6AL isn't going to gain you a lot. It will also make you car less stock which makes it harder to diagnose.

If I wanted to make power, reworking the ignition would be pretty far down the list. Provided I wasn't running points...

I finally went ahead and got a MSD 6AL with a tach adapter. Not sure if I gained anymore power but the car is definitely a lot smoother especially in the higher rpm range and I noticed a lot less fumes.